Question 70: Five dentists share a dental suite. Three work 5 days a week; one works 4 days a week; the other dentist, John, only works Fridays. There's one employee shared by the dentists, who is a receptionist. She works all 5 working days, full-time. John pays only 5% of the receptionist's salary. Would he have to treat her as a full-time employee, even though she is only working about 100 hours a year for his practice? Is there a de minimis amount, where such an employee is not considered "shared" anymore?
Answer: Your question contains a false premise, that the receptionist is only working 100 hours a year for John. Actually, she is there answering his phone 5 days a week. All day Friday she is there, soothing his patients and collecting their checks. Under common law principles and the various revenue rulings issued by the IRS, she is his full-time employee.
He pays her only 5% of her salary, it is true, but she is credited with 2,000 hours of service in connection with that 5% of her compensation.
The old revenue rulings do not contain any de minimis exception.

These issues are discussed in more detail in Chapter 5 of my book, Who's the Employer?.

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